l. Field of the Invention
This invention relates generally to ladders, specifically to equipment for enhancing the safety of ladders.
2. Description of Prior Art
Heretofore almost all types of ladders had a very unsatisfactory safety record. Perhaps the least safe were extension ladders. These are straight ladders which usually have several sliding sections; usually they are used by resting their top ends against a wall or the like. They often tended to fall, slip, collapse, etc., especially when used on uneven ground, adjacent irregular buildings, adjacent inside or outside corners of buildings, adjacent buildings with eaves, parapets, or overhanging roofs, buildings with roofs with irregular slopes, etc. When such ladders fell, slipped, rolled, etc., any workers using them also usually fell and were injured; these injuries were often serious and thus caused much pain and suffering, lost time from work, concomitant economic injury to families as well as workers, and often permanent disablement and or disfigurement.
In addition to injuries to workers, the increased litigiousness of society has created severe legal and fiscal problems for ladder manufacturers. These have become so serious that recently a national television show broadcast a lengthy feature on the problems of ladder safety, including the difficulties of obtaining liability insurance, defending lawsuits, paying large damages, adding numerous safety warnings on ladders, loss of executive time in dealing with lawsuits, etc. E.g., some executives of ladder manufacturers have been forced to spend up to 20% of their annual time dealing with lawsuits brought against their employers by injured plaintiffs. In addition, the prices of most ladders have been increased substantially to pay for increased liability insurance premiums, when available, or the increased cost of self insurance for some manufacturers since they could not even obtain insurance. Also, some ladder manufacturers have been forced out of business or into bankruptcy by huge damage judgements from lawsuits against them due to personal injuries because of falls from their ladders.
While apparatus for leveling ladders has been known for increasing stability on non-level surfaces, such apparatus has been awkward to use, install, and subject to failure or collapse in use. Anti-sway devices have been also known for use on the top of a ladder, but such devices were awkward to install, provided only slight stability, and were useful with only a small number of building configurations. Also these devices had to be installed permanently on their ladders, thereby reducing the versatility, eliminating certain applications of such ladders, and preventing other attachments from being installed on such ladders.